1. Field of the Invention (Technical Field)
The present invention relates to a method and apparatus for accurately setting micron level cutting edge stagger in a multi-tool rotating head.
2. Description of Related Art
At present there is no method of accurately setting cutting edge position so that the stagger is approximately 0.000080 inch (2 microns) between removal stages. Accordingly, there typically no stagger (no multiple-tool removal) method in rotating head tools employed for thinning ceramics (crystals), plastics, and certain metals so as to significantly minimize the time it takes to perform the thinning and finishing operations. Accordingly (because the crystals are subject to brittle fracture), 20 passes are typicality required to bring crystal thickness down from an original 0.030 inches to 0.001 inches. Material removal passes (because of slow feed rates) are usually approximately 20 minutes each.
In traditional machining, the present invention is perhaps most similar to a “shell mill”, a type of rotating head multiple pockets with pre-machined stagger around its periphery. Inserts (cutting tools) are Olen secured into the pockets as required. However, no known shell mill provides for the accuracy and adjustability of the stagger, and the designed stiffness, of the present invention.
The present invention allows accurate staggering (radially and axially) of the 3 rotating head tools, bringing production time down by 50%. (The staggers set between the three tools, and the per pass cut depth progression does not allow for a ⅔ time reduction). 6.6 hours of production time is shortened to approximately 3.2 hours.